Lagrangian Flow Networks: a new framework to study the multi-scale connectivity and the structural complexity of marine populations

Assessing the spatial structure and dynamics of marine populations, especially considering the various and interlocked scales typical of oceanic systems, is still a major challenge in Ecology. We present a novel framework based on the construction and analysis of Lagrangian Flow Network (LFNs) which results in a systematic characterization of dispersal and connectivity of early life history stages of marine organisms. The network is constructed by subdividing the basin into an ensemble of sub-regions which are interconnected through the transport of propagules by ocean currents. The analysis of such networks allows the identification of hydrodynamical provinces and the computation of connectivity proxies measuring retention and exchange of larvae at multiple scales. Due to our spatial discretization and subsequent network representation, as well as our Lagrangian approach, further methodological improvements are handily accessible. It permits a better characterization of population connectivity and allows improving the management and protection of marine ecosystems.